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61.
Hideki Kokame Kentaro Hirata Keiji Konishi Takehiro Mori 《International journal of control》2013,86(6):537-546
Supposing a non-linear system is subjected to parametric uncertainties, the present paper aims at stabilizing its unstable steady states. A distinctive feature of the problem is that exact information about the steady state is unavailable. To cope with the difficulty, we have examined the applicability of the state difference feedback which uses the difference between the present state x(t) and the past state x(t-T). A rigorous stability analysis has been executed for the case where state deviations are controllable by a single input variable. The stability analysis has led to a favourable conclusion that if the number of unstable modes is just two, and if they are not associated with the origin in the complex plane, we are always able to find a controller which stabilizes the deviations from the unknown steady state. Design process is illustrated by using two kinds of pendulum systems. 相似文献
62.
Yasuyuki Yamada Kentaro Tanaka 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(1):180-185
We report the synthesis of a novel quinone-sandwiched porphyrin in which two benzoquinones are connected oppositely at the meso positions of a porphyrin through rigid 3-amido 2,2′-bipyridine linkers. 1H-NMR and single crystal X-ray analyses revealed that the quinone-sandwiched porphyrin has a folded structure in which the porphyrin unit was inserted into the two quinone moieties via π-stacking. Insertion of a Zn(II) ion into the porphyrin center induced a drastic conformational change which is resulted in coordination of the oxygen atoms of both benzoquinone moieties to the Zn-porphyrin to afford a 6-coordinated structure. 相似文献
63.
We present a method for combining two bilingual dictionaries to make a third, using one language as a pivot. In this case
we combine a Japanese-English dictionary with a Malay-English dictionary, to produce a Japanese-Malay dictionary. Our method
differs from previous methods in its improved matching through normalization of the pivot language. We have made a prototype
dictionary of around 76,000 Japanese-Malay pairs for 50,000 Japanese head words. 相似文献
64.
Tomoya Nagira Shugo Morita Hiroyoshi Yokota Hideyuki Yasuda Christopher M. Gourlay Masato Yoshiya Akira Sugiyama Kentaro Uesugi Akihisa Takeuchi Yoshio Suzuki 《Metallurgical and Materials Transactions A》2014,45(12):5613-5623
Synchrotron X-ray radiography at 125 frames per second was used to study deformation mechanisms in semi-solid Fe-C alloys at high solid fraction and shear strain rates of 10?1/s. An image correlation approach was also used to quantify the shear strain fields and study shear-induced dilation and the origin of shear cracking. It was shown that, at high solid fraction (90 to 93 pct solid), rearrangement including rotation and translation of solid particles became restricted and shear strain localized into narrow liquid-filled channels/fissures. Shear cracking was shown to originate from inadequate liquid flow into the expanding spaces between solid particles caused by shear-induced dilation. At lower solid fraction (~85 pct solid), solid particles rearranged with a significantly higher component of rotation leading to more shear-induced dilation and a wider shear band. 相似文献
65.
Shigeo Yamabe Kazuo Kobayashi-Hattori Kentaro Kaneko Hiroshi Endo Toshichika Takita 《Food chemistry》2007,100(1):369-374
To clarify the effect of soybean varieties on isoflavone, a useful component for human health, in soybean products, we investigated changes in the isoflavone content and composition in rice-koji miso, after fermentation/aging for 6 or 12 months using varieties of soybeans (Tohoku-126, Tohoku-135, Tohoku-139, Suzuyutaka and Chinese soybeans), by high performance liquid chromatography. In soybeans, the total isoflavone content in Tohoku-126 was 444 mg/100 g, which was 1.2–2.0 times the content in the other soybean varieties. The malonyl glycosides and aglycones in soybeans accounted for more than 60% and only a few percent, respectively. As for rice-koji miso, the total isoflavone and aglycone contents were the highest in miso prepared from Tohoku-126. The ratios of glycosides to aglycones (80.1–92.6%) in miso were higher than those in the original soybeans. The time course of the isoflavone composition during the fermentation/aging process of rice-koji miso indicated that glycosides decreased from 86.4% to 44.9% after 6 months but aglycones increased from 9.6% to 53.3%. 相似文献
66.
A relationship between emission characteristics of Ba atom as an emitter material and temperature distributions of an electrode in a fluorescent lamp is described, which is measured by using laser-induced fluorescence and black-body radiation method, respectively. In a virgin lamp, a hot spot observed at the electrode edge connected to the power supply is the main source of Ba atom emission. In a long-term-used lamp, it is shown that Ba atom emission, thermionic electron emission in cathode half-cycle and electron collection in anode half-cycle are most active on the hot spot appearing on the center of the electrode. 相似文献
67.
In single-objective optimization problems, with only one optimal design objective, the absolute optimal solution to maximize/minimize the objective function can be determined. However, in most real design problems, the optimization problems are multi-objective, where two or more independent design objectives must be optimized simultaneously, and no single absolute optimal solution necessarily exists. In these cases, it is helpful for designers to recognize the range of alternative solutions that exist in Pareto-optimal sets and choose an acceptable solution from among them. In this paper, the authors carried out multi-objective optimization using Multiple Objective Genetic Algorithms through a real case study involved in indoor environmental design – the design of outer windows. Then the authors analyzed structure of Pareto-optimal solution sets. Here we present the analysis process as well as the case study details, and show how the method proposed here is effective at finding an acceptable solution for multi-objective optimization problems. 相似文献
68.
69.
Tetsuya Shishido Tomoyuki Kitano Kentaro Teramura Tsunehiro Tanaka 《Topics in Catalysis》2010,53(7-10):672-677
Nb2O5/Al2O3 catalysts calcined at high temperatures exhibited the Brønsted acid property. A monolayer of niobic acid-like compound, which has distorted octahedral symmetry, was stabilized over 16 wt% Nb2O5/Al2O3 catalyst calcined at 1,173 K. The two-dimensional Nb–O–Nb network of stabilized niobic acid-like compound probably accounts for the generation of Brønsted acid. 相似文献
70.
Dyeing wastewater collected in Kyoto city, Japan, was investigated for the occurrence of aryl hydrocarbon receptor (AhR) ligands by using an AhR-responsive reporter gene assay. Concentrated extracts of wastewater samples elicited a dose-dependent increase in AhR ligand activity, and several hydrophobic HPLC fractions of the extracts were highly effective in inducing AhR ligand activity. Three potential AhR ligands were isolated from these fractions and identified to be Disperse Red 92, Disperse Yellow 64, and 3'-hydroxybenzo[b]quinophthalone by using HPLC and LC-MS/MS. Disperse Red 92, which has also been detected in the treated effluent from a sewage plant receiving the wastewater, is an anthraquinone disperse dye showing weak AhR binding affinity in the assay. Disperse Yellow 64 and 3'-hydroxybenzo[b]quinophthalone are quinoline disperse dyes capable of activating the AhR at nanomolar concentrations. In particular, Disperse Yellow 64 is a highly potent AhR ligand that was 3 times more effective in inducing AhR ligand activity than beta-naphthoflavone in the assay. Quinoline disperse dyes are suggested to be a new class of xenobiotic AhR ligands which pose a danger to aquatic biota and human health. 相似文献